Vacuum-type converter.



W. T. BlRDSALL L.

VACUUM TYPE CONVERTER.

APPLICATION FILED OCT. 9. 1915.

1 ,,%7?,365 D Patented Sept. 3, 1918.

WITNESSES INVENTOR Wilfred T. Biro/50H,

' ATTORNEY wit-ram) n IBIRDSALL, or monronnm, new Juneau ELECTRIC AND MANUFACTURING COMPANY, A. CORPORATION OF PENNSYLVANIA. I

VACUUM-TYPE CONVERTER.

} Specification of Letters Patent.

Patented sept. i3, was.

Application filed October 9, 1915. Serial No. 54,981.

pecially free fromshort circuits and a lied phenomena.

The single. figure of the accompanying drawing'is a perspective view of a converter embodymg'my invention, together with assoand is disposed in ciated supply and regulating circuits.

In the operation'of multi-anode vacuumtype converters, there is a tendency for current-carrying particles to migrate from one anode to another and to break down the negative-electrode reluctance. of one of the anodes, thus producing short c1rcu1ts. By my invention, I so design a converter that the cathode blast is interposed between two anodes which are subject to short circuiting. Furthermore, I place a small amount of gas, which is inert withrespect to the material within the converter, such, for example, as hydrogen, nitrogen or argon 'within the container, and said gas is entrained with the cathode blast, tending to provide a rapidly moving current of gas molecules and current-carrying partic es between the anodes in question. The effect of said blast 'is' to sweep away and neutralize migratory electrons tending to pass from one anode to another, thus obviating short circuits. I am thus enabled to provide an effective shielding action without the interposition of mechanical shielding devices of the type-com-' monly employed in the prior art.

Referring to the accompanying, drawing for a more detailed understanding of my invention, .I show the container of a vacuumtype converter at 1. The container 1 is provided with a pair of main anodes 2 and 3,

a main cathode 4, and an auxiliary anode 5.

The cathode 4 is preferably composed of vaporizable reconstructing material, such, for example, as mercufi or suitable amal am e lower portion 0 the tainer 1 is filled with an inert example, as hydrogen, nitrogen or argon, at

container 1. The anodes 2 and 3 are mounted, respectively, in opposin laterally extending arms immediately a ove the cathode 4. The upper portion of the container 1 is formed into a condensing chamber of considerable size, connects the upper portion of said chamber to a point near the cathode surface. The anodes 2 and 3 are connected, respectively, to' the terminals of a source of alternating current 7, and the cathode 4 is connected to the mid-point of said source through a load 8, as is usual in the converter art. The start- 1ng anode 5 may be excited in any suitable ASSIGNOR. 'ro wnsrmanousa manner, as, for example, by connection to a terminal of the source 7 through a currentllmitlng dev1ce 9. The interior of the congas, such, for

a pressure suitable for operation in the given ap aratus.

aving thus described the construction of aconverter embodying my invention, the

operation is as follows: upon placing the device 'in operation, a cathode blast is emitted from the surface of the electrode 4 and sweeps in front of the openings leading to the anodes 2 and 3 and on into the con- Said cathode blast isdensing chamber.- made .up of molecular mercury, positive ions and electrons. By an injector action, inert gas is drawn from the tube 6 and mixes with said blast, thus adding a large number of inert gas molecules to the upwardly sweeping stream. The anodes 2 and 3 may become highly heated or, for other reasons, tend to emit current-carrying particles, in the form of either positive ions or electrons. The passage of said articles to the other anode and their violent impact thereupon mi ht result in the production of a short circuit but, in their attempted passage through the upwardly sweeping composite blast, they are either neutralized by. contact with a particle of the opposite polarity or I they are me chanically swept upward and prevented from passing across to the other anode.

the tube 6 to back to the cathode, and

lltlld tilt? posite blast betw the anodes serves as an extremely effective shielding ineans, at the same time tending to distribute the heat throughout the device and thus render its dissipation a relatively simple problem.

Because of the complex and variable nature of said blast, I shall refer to the same in certain of the claims as composed of a gaseous fluid, meaning thereby that it may be composed of a gas, a vapor, or mixtures of the two in varying proportions, the gaseous or vaporous particles being either uncharged or conveyin charges of elther polarlty.

While have shown my invention in its preferred form, it will be obvious to those skilled 'in the art that it is susceptible of various minor changes and modifications without departing from the spirit thereof and I desire, therefore, that no limitations shall be laced thereupon except such as are imposed y the rior art or are indicated in the ap ended c aims.

I cla1m as my invention:

1. In a vacuum-type converter, the com-' bination with a cathode, of a plurality of anodes disposed adjacent thereto, means for causing a cathode flame proceeding from said cathode to be projected between said anodes, andmeans for continuously supplying an inert gas to said flame, whereby a strong blast is maintained and currentcarrying particles are prevented from passing from one anode to another, with resultant short circuiting.

2. A vacuum-type converter, comprising avcontainer provided with a cathode, a plurality of anodes, and a condensing chamber located beyond said anodes with respect to j said cathode, said container being charged with aninert gas at low pressure, whereby a cathode blast proceeding from said cathode to said condensing chamber tends to continuously entrain gas particles and sweep them along therewith, forming a composite blast acting as a shield between said anodes.

3. A vacuum-type converter comprising a container provided with a cathode, a. plurality of anodes and a condensing chamber located beyond said anodes with respect to said cathode, said container being charged with an inert ga at low pressure, and a return tube from a distant point in said condensing chamber to the neighborhood of said cathode, whereby a cathode blast pro ceeding from said cathode to said condensing chamber tends to continuously entrain gas particles and sweep them along therewith, forming a resultant composite blast acting as a shield between said anodes, said gas particles returning through said tube.

4. In a vacuum-type converter charged with a small amount of inert gas, the combination with a pair of electrodes, of shielding means therebetween com rising a blast of vapor and a plurality of inert gas molecules entrained therewith.

5. In a vacuum-type converter charged with a small amount of inert gas, the com bination with a pair of electrodes between which an arc tends to form by the migration of electrons, of shielding means therebetween comprising a blast of vapor containing positive ions and a plurality of inert gas molecules entrained therewith.

6. In a vacuum-type converter charged with a small amount of inert gas, the combination with a pair of electrodes between which an arc tends to form by the mi ation of electrons, of shielding means t erebetween comprising a blast of charged particles and a plurality of inert gas molecules entrained therewith.

, In testimony whereof, I have hereunto subscribed my name this 29th day of September, 1915.

. v WILFRED T. BIRDSALL. 

